Space Junk

The upper stage of a Falcon 9 rocket crashed into the Moon on Wednesday at a speed of about 8,700 km/h. Although astronomers were prepared in advance for the historic event, no Earth telescope documented the moment of impact. The only evidence of the crash is a chemical cloud of sodium and lithium.

This is not the first time remnants of human space activity have collided with the Moon, and the phenomenon is becoming a growing concern. The impact will eject a cloud of dust and rock fragments above the lunar surface, though it will be difficult to observe from Earth without a powerful telescope.